Slit-forming device for photographic sound apparatus



96. 27, F OWENS SLIT FORMING DEVICE FOR PHOTOGRAPHIC SOUND APPARATUSFiled Nov. 26, 1929 IN VEN TOR. Fen/mm ff Owe/vs.

Patented I @ct. 2 7, 193i SLIT-FOBMING DEVICE FOR EHOTOG-r:

A CORPORATION OF NEW YOEV.

Application filed. November 26, 1929. Serial No. 409,888.

This invention relates to improvements in slit forming devices forphotographic sound apparatus, the-principal object of the inventionbeing'to provide a device of this character which is peculiarly adaptedfor use in connection with dual sound recording and reproducingapparatus, and which device is simple in construction and very efiicientin operation.

Other objects and advantages of the invention will appear as thedescription proceeds.

In the drawings accompanying this specification,

Figure 1 is a longitudinal sectional view through a device embodying thefeatures of the present invention;

Figure 2 is a longitudinal sectional view taken at right angles toFigure 1;

Figure 3 is a perspective view of a prism constituting a feature of theinvention; and

Figure 4 is a plan view of a portion of a film illustrating the soundtracks produced thereon by the device of the present invention.

Referring to the drawings, 1 designates an open-ended housing withinwhich is mounted a recording lamp 2, the base 3' of which forms asuitable closure for one end of said housing.

. The opposite end of the housing is normally such that when the latteris mounted in said member with the base of the triangle flush with oneside of the closure member 4 the apex of the triangular prism oppositesaid base will project beyond the plane of the o posite side of saidclosure member, as clear y shown in Figure 2. The said apex is cut awaycentrall of the length of the prism thereby to (livir e said prism intotwo triangular end portions connected I? a traj pezoidal centralportiomas shown in igure ,the trapezoidal portion having a vertical wallor face 6 disposed in a plane to the rear of the apices or of eac saidtriangular end portions. The said wall may be, and prefera 1y is,painted or otherwise treated to render the same 0 a ue thereby toprevent the passage of lig t therethrough, while the extreme edge of theapex endportion is ground ofi or truncated slightly to provide anoptical slit through which li 'ht may pass from the lamp 2 to a film 7suitably guided past and in contact with the said truncated apices ofthe end portions.

The closure member 4: is provided at diametrically opposite sides of thehousing with hearing brackets 8 in which are mounted for rotation a pairof film supporting rollers 9 and 10, the diameter of each of which issuch, and the bearing so located, that the perimeter of the roller willrotate through the vertical plane in which lie the truncated apices ofthe end portions of the prism. The film as it passes over the rollerswill thus pass in contact with both of the said end portions. Ifdesired, a pair of rollers 11 and 12 may be provided for engaging theside of the film opposite from the prism, said rollers being disposed atopposite sides of the prism and between it and the respective supportingrollers 9 and 10, thereby to maintain the film in iiat contact with theapices of the slit formmg prism.

It is believed that the operation of the devicewill be clear from theforegoing, taken in connection with the drawings. With the film passingover the rollers 9, 10 and in contact with the projecting end portionsof the prism, sound modulated light from the lamp 2 will pass throughthe slits formed by the truncated apices of the end portions of theprisms and will produce on the film a pair of sound record tracks 13 and14 in parallel spaced relation.

It will of course be understood that, while the invention is describedherein in connection with a recording device, it is equally applicablefor use in a reproducing apparatus, in which case a reproducing lamp andits accompanying optical system would be used, together with a 'filmhaving dual sound rec- 0rd tracks disposed in alignment with the slitforming end portions of the prism.

EREEMAN H. OWENS, OF NEW YORK, N. Y.,-ASSIGNOR T0 OWENS DEVEIZOPMENTCOR- PORATION, OF NEW YORK, 2.,

I claim:

1. In a photographic sound apparatus, a slit forming member comprising atransparent prism having a base and an apex opposite said base, andmeans for preventing passage of light through said prism from the baseto said apex at a central predetermined portion of the length of saidprism.

2. In a photographicsound apparatus, a slit forming member comprising atransparent prism having a base and an apex opposite said base, saidapex being cut away at a central predetermined portion of the length ofsaid prism thereby to form a surface parallel with the base and saidsurface being covered with an opaque material.

3.;In a photographic sound apparatus, a slit forming member comprising atransparent prism of triangular form in cross section, a portion of oneof the apices of the triangle being cut away thereby to form a surfaceparallel with the base, said surface being covered with an opaquematerial.

4:. In a photographic sound apparatus, a slit forming member comprisinga transparent prism of triangular form in cross section, said prismbeing cut away at the central portion of oneof its apices thereby toform a pair of triangular end portions connected by a central portion oftrapezoidal form and having a surface parallel .with its base, saidsurface being covered with an' opaque material.

5. In a photographic sound apparatus, the combination of an 0 en endedhousing, a lamp disposed in said housing and closing 7 one end thereof,a removable closure for the other end of the housing, said closure beingprovided with an opening therethrough extending transversely of thehousing, a transparent prism mounted in said opening and having a basedisposed in parallel relation to said closure and an apex extendingbeyond the outer surface of the closure, a predetermined portion of saidapex being cut away to form a surfaceparallel with said base, saidsurlface being covered with an opaque materia 6. Ina photographic soundapparatus, the combination of an open ended housing, a lamp disposed insaid housing and closing one end thereof, a removable closure for theother end of the housing, said closure being provided with an openingtherethrough extending transversely of the housing, a transparent prismof triangular form in cross section mounted in said opening andhavingone of its bases flush with the side of the closure nearest said lamp,the apex opposite said base extending beyond the opposite side of theclosure, said apex being cut away at the cenlel with said base, saidsurface being covered with an opaque material.

7. In a photographic sound apparatus, the combination of a transparentprism having a base and an apex opposite said base, a source of lightdisposed in position to project rays of light through said prism fromsaid base to said apex, means for preventing the passage of light at acentral predetermined portion of the prism and means for supporting atraveling film in engagement with said apex.

8. An optical slit for photographic sound recording and reproducingapparatus comprising an elongated prism, one apex of which permits thepassage of light therethrough at a plurality of spaced portions thereof,and means on said prism preventing the passage of light through theareas between said spaced portions.

'9. In combination, a light, a prism, one apex of said prism permittingthe passage of rays from said light therethrough to a traveling filmpassing said apex, and means on said prism for dividing the lightpassing therethrough into a plurality ofspaced flo beams.

In testimony whereof, I aflix my signature.

FREEMAN H. OWENS.

tral portion thereof thereby to form a pair 1

